finding probability

Question

Find the indicated probability

given

P(A)=45%

P(B)=55%

P(A and B)=35%

P(A or B)=

Answer 1

P(A^B) = .35 P(A)=.45 P(B)=.55

P(AvB)=P(A)+P(B) - P(A^B) = .45 + .55 - .35 = .65

The probability of the union = sum of the probabilities of the parts minus the probability of their intersection

In a Venn diagram it would be like two intersecting circles. Add the two circles together but subtract out where they intersect or overlap.